Conventional ball-striking implements made of plastics material have a head frame with a hollow profile, into which through-holes are drilled. Through these through-holes, the continuous string is stretched crosswise in loops. It is known that the through-holes, on the one hand, mechanically weaken the head frame and, on the other hand, chafe the string or string portions, as a result of which the string or string portions can tear there under high loads. Therefore, the through-holes are provided with individual eyes or eye bands made of a soft thermoplastic polymer.
Rackets are also known with a central strip made of thermoplastic polymer which is less hard than or as hard as the string. Hollow profiles made of fibre-reinforced plastics material are formed integrally on the central strip on both sides. The through-holes are in this case drilled into the central strip or prefabricated, for example with channels produced or pressed by injection molding.
In order to avoid these drawbacks, EP-A-0142286 discloses a tennis racket which is manufactured by injection molding and has shaped therein a wire with rectangular eyes into which the string is stretched crosswise. The rectangular eyes are in this case arranged in the plane of the impact surface. As the head frame is pear-shaped in its embodiment and the rectangular eyes are arranged with the upper rims substantially parallel to the inside of the head frame, the string is drawn during stringing into either the left or right corner of the respective eyes. It is therefore difficult, if not impossible, to achieve uniform stringing of the tennis racket. Furthermore, the respective string portions are as a result not all positioned in the same plane, as they are drawn around the eyes, making it almost impossible to achieve a stringing or impact surface that is precisely plane-parallel to the head frame.